diff --git a/docs/upgrades/upgrade_7.6.11-7.6.12.pl b/docs/upgrades/upgrade_7.6.11-7.6.12.pl
index 8e70c4ae1..322f3ff49 100644
--- a/docs/upgrades/upgrade_7.6.11-7.6.12.pl
+++ b/docs/upgrades/upgrade_7.6.11-7.6.12.pl
@@ -31,6 +31,7 @@ my $quiet; # this line required
 
 my $session = start(); # this line required
 addAssetDiscoveryServiceAgain( $session );
+changeMatrixAttributeIndexing( $session );
 
 # upgrade functions go here
 
@@ -66,7 +67,13 @@ sub addAssetDiscoveryServiceAgain {
     print "Done.\n" unless $quiet;
 }
 
-
+#----------------------------------------------------------------------------
+sub changeMatrixAttributeIndexing {
+    my $session = shift;
+    print "\tChanging Matrix attribute indexing..." unless $quiet;
+    $session->db->write("alter table MatrixListing_attribute drop primary key, add primary key(attributeId,matrixListingId)");
+    print "Done.\n" unless $quiet;
+}
 
 # -------------- DO NOT EDIT BELOW THIS LINE --------------------------------
 
diff --git a/lib/WebGUI/Asset/Wobject/Matrix.pm b/lib/WebGUI/Asset/Wobject/Matrix.pm
index ee9224368..019e488c4 100644
--- a/lib/WebGUI/Asset/Wobject/Matrix.pm
+++ b/lib/WebGUI/Asset/Wobject/Matrix.pm
@@ -965,8 +965,8 @@ assetData.revisionDate
     foreach my $result (@results){
             if($form->process("search")){
                 my $matrixListing_attributes = $session->db->buildHashRefOfHashRefs("
-                            select value, fieldType, attributeId from MatrixListing_attribute as listing
-                            left join Matrix_attribute using(attributeId)
+                            select value, fieldType, attributeId from Matrix_attribute
+                            left join MatrixListing_attribute as listing using(attributeId)
                             where listing.matrixListingId = ? order by value asc",
                             [$result->{assetId}],'attributeId');
                 PARAM: foreach my $param (@searchParams_sorted) {
@@ -1063,6 +1063,7 @@ sub www_getCompareListData {
             [$category,$self->getId,@listingIds]
         ) });
     }
+
     foreach my $result (@results){
         if($result->{fieldType} eq 'category'){
             # Row starting with a category label shows the listing name in each column
@@ -1096,8 +1097,8 @@ sub www_getCompareListData {
             }
         }
     }
-    $jsonOutput->{ResultSet} = {Result=>\@results};
 
+    $jsonOutput->{ResultSet} = {Result=>\@results};
     $session->http->setMimeType("application/json");
 
     return JSON->new->encode($jsonOutput);